考虑尺寸效应的多晶金属循环塑性分析  

ANALYSIS OF CYCLIC PLASTICITY USING A POLYCRYSTALLINE MODEL TAKING ACCOUNT OF SIZE EFFECT

作　　者：张静[1,2] 张克实[1] 许凌波[1] 

机构地区：[1]广西大学工程防灾与结构安全教育部重点实验室,南宁530004 [2]九江学院土木工程与城市建设学院,九江332005

出　　处：《固体力学学报》2012年第3期233-241,共9页Chinese Journal of Solid Mechanics

基　　金：国家自然科学基金项目(90815001;11072064);广西大学科学基金项目资助

摘　　要：采用多晶塑性分析方法,设材料单元包含一定数量的各向异性单晶晶粒并考虑晶粒尺寸的影响,利用Taylor假设计算材料单元的应力和应变.模型引入考虑尺寸效应的晶体滑移硬化函数,同时针对晶体滑移引入背应力及其方向性硬化的描述,以反映不同晶粒尺寸材料在循环加载条件下的力学行为.利用该模型,论文第一作者采用显式格式编制了与ABAQUS商用有限元软件接口的用户材料子程序(VUMAT),实例计算证实该模型可以反映和描述多晶金属材料在反复加载条件下的循环塑性行为与尺寸效应.In this contribution,a representative volume element （RVE） containing some anisotropic crystalline grains is modeled in order to analyze the plasticity behavior of polycrystal. All crystalline grains consisting of the poly-crystal are assumed to follow the Taylor＇s hypothesis. To take the grain size effect into account,a hardening function which includes both the grain size and the material characteristic length was proposed;also,a back stress model was introduced to capture the directional hardening of crystals. An explicit algorithm for the present constitutive model is developed,and then implemented into the VUMAT subroutine of ABAQUS. Finite element analyses of a pure polycrystalline copper applied to the symmetric strain cycle show that the present model can reasonably capture the grain size dependent cyclic plasticity behavior.

关 键 词：晶体塑性 尺寸效应 循环加载 应变硬化 本构关系 

分 类 号：TG111[金属学及工艺—物理冶金]